Sand source selecting structure for a sandblasting gun

ABSTRACT

A sand source selecting structure for a sandblasting gun has a main body; a channel provided in the main body, for passing a high pressure gas; at least two sub-channels provided in the main body respectively connected to the channel; a sandbox mounted on the main body connected to the channel through each of the sub-channels; at least one supply tube; a first control valve installed in the main body, for connecting the sandbox and at least one of the sub-channels of the channel; and a second control valve installed in the main body, for connecting the channel and another sub-channel of the supply tube. Therefore, the combination of the first control valve and the second valve provides a selecting structure, which can offer different sand supply sources.

BACKGROUND OF INVENTION Field of Invention

The present invention relates to a sandblasting gun, and moreparticularly to a sand source selecting structure for a sandblastinggun.

Description of the Related Art

Typical sandblasting guns spray some sand particles on the surface of ametal workpiece by high-pressure gas to perform surface treatment suchas rust removal and dustproof, thereby preventing water molecules orimpurities from adhering to the surface of the metal and preventing themetal workpiece from being rusted or damaged.

For larger metal workpieces, sandblasting guns require more sand, andsmaller metal work pieces emit less sand.

However, typical sandblasting gun is equipped with a sandbox, and thesandbox obtains a fixed amount of sand and cannot increase the amount ofsand easily.

Therefore, it is desirable to provide a sand source selecting structurefor a sandblasting gun to mitigate and/or obviate the aforementionedproblems.

SUMMARY OF THE INVENTION

An objective of present invention is to provide a sand source selectingstructure for a sandblasting gun, which is capable of improving theabove-mention problems.

In order to achieve the above mentioned objective, sand source selectingstructure for a sandblasting gun has:

-   -   a main body;    -   a channel provided in the main body, for passing a high pressure        gas;    -   at least two sub-channels provided in the main body respectively        connected to the channel;    -   a sandbox mounted on the main body connected to the channel        through each of the sub-channels;    -   at least one supply tube;    -   a first control valve installed in the main body, for connecting        the sandbox and at least one of the sub-channels of the channel;        and    -   a second control valve installed in the main body, for        connecting the channel and another sub-channel of the supply        tube.

Therefore, the combination of the first control valve and the secondvalve provides a selecting structure, which can offer different sandsupply sources.

Other objects, advantages, and novel features of invention will becomemore apparent from the following detailed description when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a structure plan view of a preferred embodiment for use with asandblasting gun according to the present invention.

FIG. 2 is a plan view of another angle of the selecting structure.

FIG. 3 is a cross-sectional view along a line A-A of FIG. 1.

FIG. 4 is an action drawing for selecting a sand source.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Please refer to FIG. 1. A sandblasting gun 10 has a main body 11, andthe main body 11 has a handgun-shaped profile. The main body 11 has achannel 12, and the channel 12 is provided with an entering end 13 andan exiting end 15, and the entering end 13 and a high pressure gasdevice (such as an air compressor) are connected by a gas pipe 14. Adetachable nozzle 16 is connected with the main body 11, and the nozzle16 is connected to the exiting end 15 of the channel 12.

A gas valve 18 is installed onto the main body 11 to intercept thechannel 12. A trigger 17 is mounted to the main body 11 and able toswing back and forth, and the trigger 17 controls the gas valve 18 tokeep the entering end 13 and the exiting end 15 of the channel 12 clear,so that the high pressure gas in the gas pipe 14 enters into the channel12. With the guidance of the nozzle 16, a gas flow 19 is injected out ofthe main body 11 outside.

As shown, a sandbox 20 is secured to the main body 11 for receiving somesand particles 22. A cover 21 locks the sandbox 20 to prevent the sand22 from exiting the sandbox 20.

Further, a selecting structure 30 is composed of a first control valve31 and a second control valve 40, and the first and second controlvalves 31, 40 are mounted on the main body 11 adjacent to the nozzle 16.

Please refer to FIG. 2 with FIG. 3. The coupling relationship betweenthe main body 11 and the first control valve 31 is described infollowing detail. The two sub-channels 112 are formed inside the mainbody 11, and the sub-channels 112 are connected to the channel 12 of themain body 11 respectively. Secondly, the first control valve 31 has afirst valve rod 33, the first valve rod 33 is provided with a knob 32and a first through aperture 35. The knob 32 is formed at one end of thefirst valve rod 33, and the first through aperture 35 connects bothsides of the first valve rod 33.

When one end of the first valve rod 33 passes through an assemblyaperture 111 of the main body 11, a pin 34 is inserted into a portionthe first valve rod 33 that exposed outside the main body 11, whichprevents the first valve rod 33 from leaving the main body 11 and notaffect the knob 32 to drive the first valve rod 33 to rotate around themain body 11. In addition, a set of the first O ring 36 is embedded inthe surface of the first valve rod 33 around the first through aperture35 while contacting the main body 11 to form a wall for the assemblyaperture 111, thereby providing sealing effect to prevent pressureleakage.

In a preferred embodiment, the main body 11 further has a baffle 113protruding out from the surface and disposed on two sides of the firstvalve rod 33, and the baffle 113 blocks the pin 34 and limits the firstvalve rod 33 to only move in longitudinal and lateral positions.

When the first valve rod 33 is at the longitudinal position, the axialdirection of the first through aperture 35 is substantially parallel tothe length direction of the sub-channel 112, so the sub-channel 112 isopened. Therefore, the high pressure gas in the channel 12 producessuction to the sub-channel 112. Since the sandbox 20 is internallyconnected to the sub-channel 112, the sand in the sandbox 20 is mixedwith high pressure gas in the sub-channel 112 along the direction ofarrow 221 and is injected together to the outside of the main body 11via the channel 12.

As shown in FIG. 4, in the lateral position, the axial direction of thefirst through aperture 35 is substantially perpendicular to the lengthdirection of the sub-channel 112, so the sub-channel 112 is cut-off bythe surface of the first valve rod 33. Therefore, the high pressure gasin the channel 12 does not make effect on the sandbox 20, and the sandof the sandbox 20 naturally does not enter the channel 12.

In other words, the first control valve 31 controls whether the sand inthe sandbox 20 enters the channel 12 or not.

Next, please refer to FIGS. 2 and 4. The main body 11 has a protrudingportion 114, the protruding portion 114 and the sandbox 20 are disposedon either side of the main body 11, and another sub-channel 112 extendsthrough the interior of the protruding portion 114. Furthermore, thesecond control valve 40 is composed of a second valve rod 42 and aconnector 50. The second valve rod 42 is substantially identical withthe first valve rod 33, and also has a second knob 41, a second throughaperture 44 and a second O ring 45. The connector 50 has an insertingportion 51, and the inserting portion 51 is a round tube and has aninner chamber 52.

When the connector 50 is sleeved onto the protruding portion 114, andthe second valve rod 42 passes through the protruding portion 114 andthe connector 50. Moreover, a second pin 43 is inserted into a portionof the second valve rod 42 exposed outside the connector 50, thereforethe connector 50 can be prevented from leaving the protruding portion114 without affecting the second knob 41 to drive the second valve rod42 to rotate relative to the connector 50. Additionally, a baffle 53protrudes from the surface of the connector 50, since the second pin 43limits the movement of the second valve rod 42 back and forth in thelongitudinal and lateral positions, the second O ring 45 touches theprotruding portion 114 (or the connector 50) and also has a sealingeffect that prevents pressure leakage.

An opening of a hose 23 is jacketed onto the inserting portion 51, andthe inner chamber 52 of the inserting portion 51 is connected to thehose 23. Another opening of the hose 23 is connected to a rigid tube 24inserted into the sand pile 25 (see FIG. 1).

When the second valve rod 42 is at the longitudinal position, the axialdirection of the second through aperture 44 is also parallel to thelength direction of the sub-channel 112, so the sub-channel 112 isopened. The high pressure gas in the channel 12 generates suction to thesand pile 25 (see FIG. 1) through the hose 23 and the rigid tube 24, sothat the sand particles are mixed with the high pressure gas and sprayedout of the main body 11 via the channel 12 as the direction of the arrow251.

As shown in FIG. 3, when the second valve rod 42 is at the lateralposition, the axial direction of the second through aperture 44 issubstantially perpendicular to the length direction of the sub-channel112, therefore the sub-channel 112 is cut-off by the surface of thesecond valve rod 42. The high pressure gas is blocked by the secondvalve rod 42 and has no effect on the sand pile 25 (see FIG. 1), and thesand naturally does not enter the channel 12 via the hose 23.

Basically, the second control valve 40 is the controller that controlsthe high pressure gas in the channel 12 to extract the sand pile 25 (seeFIG. 1) through the hard tube and the hose 23.

Even the first control valve 31 and the second control valve 40 areindependent of each other and can be turned on and off respectively, butsimultaneously turning on or off the first and second control valves 31,40 should still be applied within range of the present invention.

Although the present invention has been explained in relation to itspreferred embodiment, it is to be understood that many other possiblemodifications and variations can be made without departing from thespirit and scope of invention as hereinafter claimed.

What is claimed is:
 1. A sand source selecting structure for a sandblasting gun comprising: a main body; a channel provided in the main body, for passing a high pressure gas; at least two sub-channels provided in the main body respectively connected to the channel; a sandbox mounted on the main body connected to the channel through each of the sub-channels; at least one supply tube; a first control valve installed in the main body, for connecting the sandbox and at least one of the sub-channels of the channel; and a second control valve installed in the main body, for connecting the channel and another sub-channel of the supply tube.
 2. The sand source selecting structure of a sandblasting gun as claimed in claim 1, wherein the first control valve further comprises a first valve rod with a first through aperture, the first valve rod is placed in the main body, the first through aperture is parallel or perpendicular with the sub-channel, and the first control valve controls the sub-channel.
 3. The sand source selecting structure of a sandblasting gun as claimed in claim 2, wherein the first control valve further comprises a knob and a pin, the knob and the pin are respectively disposed at two ends of the first valve rod, and the pin engages a baffle of the main body to limit the first valve rod.
 4. The sand source selecting structure of a sandblasting gun as claimed in claim 2, wherein a first O ring is disposed around the first through aperture, and the first O ring makes contact with the first valve rod and the main body for a sealing purpose.
 5. The sand source selecting structure of a sandblasting gun as claimed in claim 1, wherein the second control valve comprises: a second valve rod with a second through aperture; and a connector having an inserting portion with an inner chamber, the inserting portion engaging the supply tube, and the inner chamber is connected to the supply tube and the sub-channel; wherein when the connector jackets onto a protruding portion of the main body, the second valve rod passes the protruding portion and the connector, the second through aperture is parallel or perpendicular with the sub-channel, and the second control valve controls the sub-channel.
 6. The sand source selecting structure of a sandblasting gun as claimed in claim 5, wherein the second control valve further comprises a second knob and a second pin, the second knob and the second pin are disposed at two ends of the second valve rod, the second pin engages with a baffle of the of the connector to limit the second valve rod.
 7. The sand source selecting structure of a sandblasting gun as claimed in claim 5, wherein a second O ring is disposed around the second through aperture, and the second O ring makes contact with the second valve rod and the protruding portion for a sealing purpose. 